Turner’s notes run down the left-hand side of the page:
Pycnostyle 1 or 1 ½ diam | Systylos 2 2 ½ | Diastyle 3 | Areostyle 4 5 6 | Anta front of the Pilasters | Prostylos 2 columns against the | Pilasters at the corners | Amphiprostylos | Peripteros | Pseudodipteros | Dipteros | <Hypæt> Hypæthos: [‘r’ inserted above between ‘h’ and ‘o’, i.e. ‘Hypæthros’] uncoverd to the | Air
Maurice Davies has identified these terms as coming from the 1598 English edition of Giovanni Paolo Lomazzo’s Tracte Containing the Artes of Curious Paintinge Carvinge & Buildinge (see the sketchbook Introduction).1 They are from chapter XXIX, ‘Of the Intercolumneations [sic] of the Columnes in Respect of Themselves, and of their Dimensions, and Aspectes’ of ‘The First Booke: Of the Naturall and Artificiall Proportions of Things’, pages 104 (to ‘4 5 6’), 106 (to ‘Peripteros’), and 107. Lomazzo gives the terms as a series of headings, each with a short paragraph of explanation from which Turner has noted the fundamental points.
Intercolumniation is the spacing between classical columns expressed as units of their diameters, as set out by the Roman architectural writer Vitruvius; the list continues with the names of ground plans of Greek temples in terms of the arrangement of their columns.2 Lastly, a hypaethros is a type of opening in a temple roof. A number of Turner’s perspective lecture diagrams (Tate; Turner Bequest CXCV) show plans and elevations of classical architecture.